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  <title>Document</title>
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  <script>

    var timeString = "03/23/2033"

    // 1.方式一:
    // var date = new Date(timeString)
    // var timestamp = date.getTime()

    // 2.方式二:
    var timestamp = Date.parse(timeString)
    console.log(timestamp)

  </script>

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